<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
    /*    window.color = "red";
        //let 声明的全局变量不具有全局属性，即不能用window.访问
        let color = "green";


        let obj = {
            color: "blue",
            getColor: () => {
                return this.color;//this指向window
            }
        };

        let sayColor = () => {
            return this.color;//this指向window
        };
        console.log(sayColor());

        console.log(obj.getColor());
*/


      /*  (function () {
             aa = 3;
            alert(aa);
        })();*/

   /* var a=11
    function test1(){
        this.a=22;
        let b=function(){
            console.log(this);
            console.log(this.a);
        };
        b();

    }
    var x=new test1();*/
    for (let i = 0; i < 10; i ++) {
        console.log(i);
    }
    console.log(i);//Uncaught ReferenceError: i is not defined at <anonymous>:4:13


    </script>
</head>
<body>
<select name="" id="" style="width: 200px;text-align: center;display: inline-block">
    <option value="">12</option>
    <option value="">12</option>
    <option value="">12</option>
    <option value="">12</option>
</select>
</body>
</html>